PuppetCA not signing Certificate-Requests

I'm having a setup with MCollective 1.2.0, Puppet 2.6.4 and an provision-agent. Most of the time this works great, but sometimes (every 10th node or so) I experience, that signing-requests of puppet- agents are not getting signed on the master. In this case every request of the puppet agent to the "/production/certificate/..." fails with an HTTP-Error 404.

The problem is also hard to analyze because the logoutput is not very detailed.

Puppet-Agent:

Jun 18 16:10:3开发者_如何学运维8 ip-10-242-62-183 puppet-agent[1001]: Creating a new SSL key for ...

Jun 18 16:10:38 ip-10-242-62-183 puppet-agent[1001]: Caching certificate for ca

Jun 18 16:10:41 ip-10-242-62-183 puppet-agent[1001]: Creating a new SSL certificate request for ...

Jun 18 16:10:41 ip-10-242-62-183 puppet-agent[1001]: Certificate

Request fingerprint (md5): 6A:3F:63:8A:59:2C:F6:C9:5E:56:5F:39:16:FF:19:BE

Puppet-Master:

"GET /production/certificate/a.b.c.d HTTP/1.1" 404

"GET /production/certificate_request/a.b.c.d HTTP/1.1" 404

"GET /production/certificate/a.b.c.d HTTP/1.1" 404

"GET /production/certificate/a.b.c.d HTTP/1.1" 404

"GET /production/certificate/a.b.c.d HTTP/1.1" 404

"GET /production/certificate/a.b.c.d HTTP/1.1" 404

... last message repeats endlessly

Does anyone have a glue about that?

Markus